<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<script src="jquery/1.10.2/jquery.min.js">
	
</script>
<script>
	$(document).ready(function() {
		$("#btn1").click(function() {
			$("img").before("<b>之前</b>");
		});

		$("#btn2").click(function() {
			$("img").after("<i>之后</i>");
		});
	});
</script>
</head>

<body>
	<img src="/images/logo.png">
	<br>
	<br>
	<button id="btn1">之前插入</button>
	<button id="btn2">之后插入</button>
</body>
</html>